Chapter 9: X-ray Fluorescence Applications in Agriculture

Advancements in X-Ray Fluorescence (XRF) spectroscopy over the past decade have transformed the technique from laboratory based standalone units to highly portable and lightweight portable XRF (pXRF) spectrometers. While pXRF spectrometers can greatly increase access to technology and simplify data collection, appropriate selection of analysis conditions and interpretation of the data generated still require a detailed understanding of the principles of X-ray spectrometry. Often, pXRF instruments are sold and used as rapid “point and shoot” solutions for materials analysis problems to users with little training in X-ray physics and spectrometry, and the identification of instrument artifacts. These pXRF spectrometers have applications in agricultural fields providing the opportunity to study many of the materials encountered in the field with greater flexibility than ever before. This chapter is meant to be a guide that presents and addresses current problems in soils and agro-input analyses using pXRF, with particular emphasis on how World Agroforestry (ICRAF) uses these systems for agricultural applications, the challenges confronted when characterizing these materials and the methodologies used to overcome some of the issues, and discussions on the issues that cannot currently be resolved using this technique alone.